Liquid tank



FIG. 1 is an isometric view from the front, left and top of a liquid tank showing my new design;

FIG. 2 is an isometric view from the rear, right and top thereof;

FIG. 3 is a front elevational view thereof;

FIG. 4 is a right side elevational view;

FIG. 5 is a top view thereof;

FIG. 6 is a rear elevational view thereof; and,

FIG. 7 is a bottom view thereof. 

CLAIM The ornamental design for a liquid tank, as shown and described. 